Flattener for tube bender



Dec. 16, 1969 P. v. GREGG 3,483,725

FLATTENER FOR TUBE BENDER Filed Oct. 1l.' 1967 2 Sheets-Sheet l Dec. 16., 1969 P. v. GREG@ 3,483,725

FLATTENER FOR TUBE BENDER Filed Oct. 1l. 1967 2 Sheets-Sheet 2 I Il Il :://7

INVENTOR.

7&5 y y 576W nted States Patent O 3,483,725 FLATTENER FOR TUBE BENDER Paul V. Gregg, Racine, Wis., assigner to Walker Manufacturing Company, Racine, Wis., a corporation of Delaware Filed Oct. 11, 1967, Ser. No. 674,394 Int. Cl. B21d 7/02 US. Cl. 72--384 4 Claims ABSTRACT F THE DISCLOSURE Adapters comprising a channel-shaped, fixed position die and a fiat surfaced punch are provided which can be secured in proper position to the ram and to the pivotal wing die plates of a conventional pipe 'bending machine and used to flatten a side of a tube.

BRIEF SUMMARY OF THE INVENTION In the bending of pipes 'for use in automotive exhaust systems it is often necessary to flatten a selected length of the pipe in order to enable it to clear obstructions in the automobile structure when the pipe is installed as a part of an exhaust system. Such pipes always have one or more bends formed in them and it has been necessary to use separate machine tools to bend and to form the flat section on the pipe. It is the purpose of this invention to provide relatively simple adapter structure which may be mounted in place on a conventional pipe bender machine 'to enable the bender to also be used to flatten the pipe.

The invention provides adapter iixtures which include relatively movable parts one of which can be secured to the movable wing die plate of a bender and the other of which remains in a fixed position so that it can support a channel shaped iiattening die during a flattening operation performed by flattening punch that may be attached to the ram of the bender.

DESCRIPTION OF THE DRAWINGS FIGURE l is a somewhat schematic perspective view with parts removed of a bending machine embodying the invention;

FIGURE 1A is a cross section of a pipe as it may be flattened by means of the invention;

FIGURE 2 is a side view taken from the left of FIG- URE 1;

FIGURE 3 is an enlarged view illustrating relative movement between different parts of the adapter structure;

FIGURE 4 is a front view partly broken away of the ram carrying the pipe bending ram die and the pipe flattening punch; and

FIGURE 5 is an enlarged front elevation partly broken away of the adapter structure.

DESCRIPTION OF THE INV ENTION A conventional pipe bending machine 1 as sold by the Pine Engineering Company, has a ram 3 and a pair of wing die plates 5 and 7 which are mounted on the frame of the machine (not shown) by means of spindles or pins such as 9 so that the horizontal plate sections 11 and 13 can pivot downwardly as indicated by the arrows in FIGURE 1. The wing die plates carry a pair of wing dies 15 and 17 which contain aligned semi-circular recesses that cooperate with a semi-circular recess in the semi-circular bending punch 19 that is carried by the ram 3.

In use as a. bender, a piece of pipe is placed in dies 15 and 17 when they are transversely aligned as in FIGURE 1 and then the ram 3 is lowered to engage the 3,483,725 Patented Dec. 16, 1969 ICC pipe. The force of the ram causes the wing die plates 11 and 13 to pivot outwardly in the direction of the arrows so that the pipe is wrapped around the curvature of the recess in the punch 19 and a bend is formed. The foregoing is conventional press bending structure and operation.

In accordance with this invention adapter structures 21 and 23 are mounted on the horizontal sections 11 and 13 of the wing die plates. The adapter structures include support blocks 25 and 27 which are rigidly secured by bolting to the plates 11 and 13. The support blocks include top support surfaces 29 and 31 which are flat but extending upwardly from the outer ends of each surface are pairs of lugs or projections 33 and 35, the projections in each pair being spaced apart.

Supported on the surfaces 29 and 31 are adapter plates 37 and 39 and these have projections 41 and 43 which fit respectively between the pairs of lugs 33 and 35. A pivot pin 45 pivotally connects the projection 41 to the lugs 33 and a pivot pin 47 pivotally connects the projection 43 to the lugs 45.

The top faces 49 and 51 of the plates 37 and 39 are at and coplanar and contain T-slots 53 whereby a flattening die 67 may be rigidly secured to the plates 37 and 39 by means of T-bolts in conventional fashion. The die support plates 37 and 39 are maintained in aligned fixed position by means of alignment pin 57 which fits in aligned bores 59 and 61 in the two plates as best seen in FIGURES 3 and 5. A set screw 63 engages a at 65 on the pin 57 to hold it in position in plate 39.

The flattening die block 67 is bolted against the top faces 49 and 51 and is therefore held in rigid horizontal position by the plates 37 and 39 throughout operation of the bender 1. When the wing die plates 11 and 13 pivot downwardly the support blocks 25 and 27 also pivot but due to the relative movement provided by the pins 45 and 47 the plates 37 and 39 remain in the horizontal position.

Flattening of the pipe P as seen in FIGURE 1A from the dotted to full line shape is accomplished by placing the pipe in the die 67 directly beneath a flattening punch 69 that is secured `by conventional means 71 to the ram 3 in place of a second bending. When the ram 3 is lowered the flat bottom face 73 of the punch 69 engages the pipe and fiattens it to the shape desired. Since the force required to f'latten the pipe is insutiicient to bend the pin 57, the flattening operation can be accomplished even though the wing dies 11 and 13 pivot to some degree, however, it is desirable to adjust the machine 1, where possible, so that pivoting of the wing supports does not occur during a flattening operation.

It is apparent that the adapter structure can accommodate iiattening dies 67 of different sizes and lengths. The tie pin 57 will also permit the adapter structure to be used on different machines where the spacing between the wing die pivots 9 may be greater or lesser than the particular machine illustrated since the die pin can move in and out of the die support plates.

Modifications may be made without departing from the spirit and scope of the invention.

I claim:

1. Adapter structure to provide for iiattening of a tube on a tube bending machine having a ram and a pair of pivotal wing dies comprising, a attening punch for attachment to the ram of the machine, a flattening die to hold a pipe for attening by said punch, and support means mounted on the two wing dies for holding the flattening die in a fixed position.

2. Structure as set forth in claim 1 wherein said support means comprises a bed means and a mounting means, said flattening die being secured to said bed means, said mounting means comprising a pair of mem- 3 Y 4 bers secured respectively to each of said wing dies to References Cited ailiifgtmtirgegth, said bed means being pivoted to both Y UNITED STATES PATENTS 3. Structure as set forth in claim 2 wherein said bed 3,266,287 8/1966 Gini 72-470 means comprises a pair of plates pivoted respectively to each of said members, and means for aligning said 5 CHARLES W- LANHAM Primary Examiner pair of plates. L. A. LARSON, Assistant Examiner 4. Structure as set forth in claim 3 wherein said aligning means comprises a dowel pin extending into both U.S, Cl. X.R. plates. 72-472, 474 

